System and method for displaying seismic horizons with attributes

ABSTRACT

A system and method may, based on a 3D seismic data set seed point, execute a seed picking algorithm, using the first point for picking a set of second points from the data set, setting each of the points in the set of second points as the first point and repeating the algorithm. An iteration number or other attribute may be assigned to the points, the iteration number corresponding to the number of times the algorithm repeated to process the point. The attribute or a number of attributes may be displayed as a visual characteristic for each point. An iterative process may be applied to a set of seismic data points, starting at a seed data point and finding a set of next iteration seed points from among the set of points neighboring the seed point, continuing only with next iteration seed points, and recording for each of a set of data points the number of points that are found by the process when the point is used as a seed data point. Attributes may include, for example, the total number of descendants of a seed point, the direction, for example, the azimuth, of propagation of the horizon picking process, or information that relates to the order in which points are picked such as an iteration number.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is continuation of U.S. application Ser. No. 12/090,584filed on Apr. 17, 2008, which is a national Stage application ofInternational Application PCT/IL2006/001211, filed on Oct. 19, 2006,which claims priority from U.S. Provisional application 60/728,765,filed on Oct. 21, 2005, each of which is incorporated by referenceherein in its entirety.

FIELD OF INVENTION

The present invention relates generally to the field ofthree-dimensional (3D) seismic data presentation and interpretation.Specifically, it relates to a system and method for displaying theprogress or result of 3D seismic horizon picking process.

BACKGROUND OF THE INVENTION

A horizon map, which is a presentation of a three-dimensional (3D)seismic data, may provide users, typically, for example, petroleumexploration professionals, with certain level of understanding of thegeology and geometry of the subsurface of the earth. With recentprogress in computer-aided oil exploration and oil field development,there is commercially available software that uses well-known algorithmsto create a horizon starting from one or more initial seed pointsprovided by a user. A horizon may be defined as for example atopographic representation of underground strata which may be forexample calculated or determined from 3D volume data. A horizon may be achange in lithology in the crust of earth or a chronostratigraphicboundary represented in a 3D seismic volume by a characteristic traceshape over certain time or depth interval. A horizon created by analgorithm may be displayed on computer monitor screen, and usually is anx-y display including the seed points and other points, that may beknown as ‘picked points’, derived by the algorithm from the seed points(or “seeds”) and the 3D seismic data. For example, horizon generatingand display systems are shown in U.S. Pat. No. 5,570,106, entitled“Method and Apparatus for Creating Horizons From 3-D Seismic Data,”(attached hereto as Appendix A) and U.S. Pat. No. 5,615,171, entitled“Method and Apparatus for Finding Horizons in 3-D Seismic Data,”(attached hereto as Appendix B) each of which incorporated by referenceherein in their entirety.

SUMMARY OF THE INVENTION

Embodiments according to the present invention may provide a system andmethod for accepting a first point from a 3D seismic data set, executinga seed picking algorithm, using the first point for picking a set ofsecond points from the data set, setting each of the points in the setof second points as the first point and repeating the algorithm, andassigning an iteration number to each of the points, the iterationnumber corresponding to the number of times the algorithm repeated,applied or executed to pick or process the point.

Embodiments according to the present invention may provide a system andmethod for processing 3D seismic data, including applying an iterativeprocess to a set of seismic data points, the process starting at a seeddata point, each iteration in the process corresponding to an iterationnumber, where at each iteration the process is applied to pointsneighboring the points currently being processed, and recording for aset of data points the iteration number in which the point wasprocessed.

Embodiments according to the present invention may provide a system andmethod for processing 3D seismic data, including applying an iterativeprocess to a set of seismic data points, the process starting at a seeddata point and finding a set of next iteration seed points from amongthe set of points neighboring the seed point, the process continuingonly with next iteration seed points, and recording for each of a set ofdata points the number of points that are found by the process when thepoint is used as a seed data point.

Embodiments of the invention provide a system, which may be for examplea computer system, and a method, which may be a computerized method, forpicking horizons from a 3D volume of seismic traces, and for displayingprogress or result of the order of progression including for exampledefinition, calculation, storage and display of seismic attributes.Visual and/or graphic representation of the attributes may be forexample color, brightness, etc. For example, each range of attributesmay be assigned a color.

Embodiments of the invention provide a system and a method of automatedhorizon picking in a 3D volume of seismic data. The process of creatinga horizon, horizon picking, may start at one or more seed locations andprogress through the 3D seismic volume by comparing the seed and shapesof traces to be picked potentially over some time interval and bychoosing the relatively similar, preferably the most similar, pick traceshape at each step. Examples of creating horizons are described in theabove mentioned U.S. Pat. No. 5,570,106, and U.S. Pat. No. 5,615,171;however other methods of calculating or determining horizons may beused.

Embodiments of the invention may provide a system and a method to storeattribute information at one or more, or each, picked points of ahorizon, wherein the attribute information may include for example thenumber of steps or iterations between an original seed point and thepicked points following the progression of a picking algorithm.

Embodiments of the invention may provide a system and a method to storeattribute information at one or more, or each, picked points of ahorizon, wherein the attribute information may include the number offurther points being picked that result from the one or more pickedpoints.

Embodiments of the invention may provide a system and a method to storeattribute information at one or more, or each, picked points, whereinthe attribute information may include the azimuth of propagation at theone or more picked points that are the mean of directions of theprogression to, and the progression from, the one or more picked points.

Embodiments of the invention may provide a system and a method todisplay the attributes or derivatives of the attributes individually asa horizon map or surface.

Embodiments of the invention may provide a system and a method todisplay the attributes or derivatives of the attributes in combinationwith each other or other horizon attributes as horizon maps or surfaces.

BRIEF DESCRIPTION OF THE DRAWINGS

The principles and operation of the system, apparatus, and methodaccording to embodiments of the present invention may be betterunderstood with reference to the drawings, and the followingdescription, it being understood that these drawings are given forillustrative purposes only and are not meant to be limiting.

FIG. 1 depicts a computer system able to record attributes and displayhorizon maps with selective attributes according to one embodiment ofthe invention;

FIG. 2 is a graphical illustration of an attribute map displayed with ahorizon map, according to one embodiment of the invention;

FIG. 3 is a graphical illustration of an attribute map and a horizonmap, generated according to an embodiment of the invention;

FIG. 4 is a graphical illustration of an attribute map and a horizonmap, generated according to an embodiment of the invention;

FIG. 5 is a graphical illustration of an attribute map displayed with ahorizon map, according to one embodiment of the invention;

FIG. 6 is a graphical illustration of an attribute map and a horizonmap, generated according to an embodiment of the invention; and

FIG. 7 is a flowchart illustration of a method for recording andpresenting horizon maps with selective attributes according to oneembodiment of the invention.

For simplicity and clarity of illustration, elements shown in thedrawings have not necessarily been drawn to scale. For example, thedimensions of some of the elements may be exaggerated relative to otherelements for clarity. Further, where considered appropriate, referencenumerals may be repeated among the drawings to indicate corresponding oranalogous elements throughout the serial views.

DETAILED EMBODIMENTS OF THE INVENTION

In the following description, various aspects of the present inventionwill be described. For purposes of explanation, specific configurationsand details are set forth in order to provide a thorough understandingof the present invention. However, it will also be apparent to oneskilled in the art that the present invention may be practiced withoutthe specific details presented herein. Furthermore, well-known featuresmay be omitted or simplified in order not to obscure the presentinvention.

Embodiments of the present invention may include, at least in part,apparatuses for performing the operations herein, such as computers,workstations, processors, networks of such devices, or other computingor calculating systems. Such apparatuses may be specially constructedfor the desired purposes or may include general purpose computersselectively activated or reconfigured by a computer program stored inthe computers. Such computer programs may be stored in a computerreadable storage medium, such as, but is not limited to, any type ofdisk including floppy disks, optical disks, CD-ROMs, magnetic-opticaldisks, read-only memories (ROMs), random access memories (RAMs),electrically programmable read-only memories (EPROMs), electricallyerasable and programmable read only memories (EEPROMs), magnetic oroptical cards, or any other type of media suitable for storingelectronic instructions.

The methods and/or processes presented herein are not inherently relatedto any particular computer or other apparatus. Various general-purposesystems may be used with programs in accordance with the teachingsherein, or it may prove convenient to construct a more specializedapparatus to perform the desired method. Embodiments of the presentinvention are not described with reference to any particular programminglanguage. It will be appreciated that a variety of programming languagesmay be used to implement the teachings of the invention as describedherein.

Unless specifically stated otherwise, as apparent from the discussionsherein, it is appreciated that throughout the specification discussionsutilizing terms such as “processing”, “computing”, “calculating”,“determining”, or the like, typically refer to the action and/orprocesses of a computer or computing system, or similar electroniccomputing device that manipulates and/or transforms data represented asphysical, such as electronic, quantities within the computing system'sregisters and/or memories into other data similarly represented asphysical quantities within the computing system's memories, registers orother such information storage, transmission or display devices.

FIG. 1 depicts a computer system able to record attributes and displayhorizon maps with selective attributes according to one embodiment ofthe invention.

As illustrated in FIG. 1, a computer system 100 may have a processor101, a memory 111, and access to and/or include software 102 executed byprocessor 101. Software 102 may be a horizon picking module, as is knownin the art, that may, for example, pick points from a 3D volume ofseismic data 103 to form a horizon map 104. The process of horizonpicking by software 102 may include applying an iterative process oralgorithm to a set of seismic data points, for example, using seismicdata 103, stored in, e.g., memory 111. For example, software 102 mayexecute a seed picking algorithm, starting at one or more seed or startpoints of seismic data 103 and may progress through the volume ofseismic data 103. In one embodiment, the iterative algorithm may comparethe seeds and potential pick trace's shapes over some interval andchoose the most similar pick trace shape at each step.

Software 102 may start at a point of seismic data 103 that may beprovided manually be a user or automatically by the seed pickingalgorithm or by any other means. In some embodiments, software 102 maychoose a set of next iteration seed points from among a set of pointsneighboring the seed point in seismic data 103. Software 102 may applythe iterative process may apply the chosen set of next iteration seedpoints.

In a demonstrative embodiment, software 102 may execute a seed pickingalgorithm using a first point of seismic data 103 for picking a secondpoint from seismic data 103. The second point is typically picked fromthe neighbors of the seed point; or from the neighbors of the seed pointthat have not themselves been processed (to avoid backtracking). Thesecond point or set of points may be considered a seed point during thenext iteration. Software 102 may repeat the algorithm, executing theseed picking algorithm using the second point of seismic data 103 forpicking a third point from seismic data 103, and so on. Such processesmay be used to generate horizon map 104. Each point thus may correspondto an iteration (e.g., to an integer number corresponding to the numberof iterations). Each point may also have associated with it all pointsthat were found by the algorithm when that point was a seed point—e.g.,each point, if the algorithm finds points based on that point, may be aparent point to one or many child points, which themselves can beconsidered seed points.

Along the progression of horizon picking, certain attributes associatedwith the propagation or status of horizon picking process at a pickedpoint of seismic data 103 may be recorded, for example, the total numberof descendants of a seed point, the direction, for example, the azimuth,of propagation of the horizon picking process, information that relatesto the order in which points are picked such as an iteration number, orthe number of descendants found using the horizon picking process on aseed point. Such information, such as, attributes 110 associated withpoints, may be stored, e.g., in memory 111. Values for multiple types ofattributes 110 may be recorded for a picked point. Attributes 110 mayinclude, for example, a rate or change in the rate of the picking ofpoints, a direction of propagation that a picking algorithm pickspoints, the number of steps, iterations, or repetitions of the seedpicking algorithm executed using a start point to pick the picked point,generations between an original seed or start points and the pickedpoint, and/or the number of points being picked from a previously pickedand/or start point (e.g., the number of points found when a point wasused as a seed point), and/or the azimuth or other measure of specialorientation. Information relating to an attribute value of a point maybe displayed to the user, for example, as a visual representation of thevalue associated with each point or may alter the presentation of apoint. For example a number of generations or picks, or a range of thesenumbers, may be associated with a visual representation such as color,brightness, etc. A point may be displayed according to its attribute,e.g., as a color depending on the attribute 110.

According to one embodiment of the invention, software 102 mayselectively present attribute map 106, displaying recorded attributedata associated with one or more attributes of points picked fromseismic data 103, or displaying points according to their attributes,for example, using a known seed picking algorithm. Attribute map 106 maybe displayed adjacently or concurrently with, overlaid on, in place of,or substantially simultaneous to, horizon map 104. Concurrent displayingof seismic data and attribute data may provide insightful information toa user, for example, a petroleum exploration professional.

In some embodiments, attribute map 106 may be generated after thecompletion of horizon picking process. In other embodiments, attributemap 106 may be generated during the horizon picking process. Forexample, an attribute may be assigned to a picked point and/or mappedinto attribute map 106 substantially simultaneously to the picking ofthe point, or during a time period substantially independent of thetiming of subsequent seed picking steps.

In some embodiments, a petroleum exploration professional may interactwith software 102 through a user interface 105, which may be a graphicuser-interface (GUI) for example, to provide instructions to software102 to process, for example, calculating derivatives of, the attributes,and/or make selections of the attributes to be displayed. User-interface105 may also enable a professional to selectively choose attributes tobe recorded and/or displayed during the process of point picking forhorizon map 104. In a demonstrative embodiment, a plurality of differenttypes of attributes, associated with picked point of seismic data 103,may be recorded. A distinct attribute map 106 may be generated for eachof the plurality of attributes 110. User-interface 105 may include anattribute selection interface 107. Attribute selection interface 107 mayallow a user to select which one or more of the plurality of attributes110 and/or corresponding attribute maps 106 are to be displayed in userinterface 105. Attribute selection interface 107 may allow the user tocustomize the manner in which the selected attribute maps 106 aredisplayed. Attribute selection interface 107 may allow the user toassign to each of a plurality of attributes, values of attributes, orranges of attributes, different visual representations, for example,color, brightness, dots, columns, translucency, lines, etc. Attributeselection interface 107 may receive such selections or user input viainput devices 108 and/or 109. In one embodiment, attribute map 106 maybe overlaid onto horizon map 104 with values indicated by colorvariations or variations in other visual representations.

In some embodiments, attribute maps 106 may be hidden and/or revealed atthe command of a user. Attribute selection interface 107 may allow theuser to decide to hide or display horizon map 104 and/or each ofattribute maps 106. Attribute selection interface 107 may offer the userother options.

FIG. 2 is a graphical illustration of an attribute map displayed with ahorizon map, according to one embodiment of the invention. An attributemap 106 may provide and/or display data associated with values or valueranges for one or more of attributes 110 corresponding to points pickedfrom seismic data 103. Attribute map 106 may include regions 210, 220,and 230, including points picked from seismic data 103 with values forattribute 110 that fall within value ranges A, B, and C, respectively.In one embodiment, each of value ranges A, B, and C may be assigned adifferent level or sub-range of a visual representation, for example, aconcentration or density of dots, a height of columns, a level oftranslucency, a difference in color or brightness of dots or points, adifference in the color or brightness of multiple lines, a width of thelines, or other suitable visual representations of attributes. Othervisual variations and/or representations may be used to distinguishdifferent value ranges A, B, and C and regions 210, 220, and 230. Othernumbers of representations of attributes may be used. For example, arange of 256 colors may be used to represent a range of attributes.

Regions 210, 220, and 230, may each include different levels of visualrepresentations corresponding to a different value range for attribute110. Attribute map 106, for example, overlaid on, horizon map 104, mayindicate an average value change of attribute 110 for points picked fromseismic data 103.

In one embodiment, attribute 110 may include a number of iterations of aseed picking algorithm for picking a point from a start point. Valueranges A, B, and C, may be, for example, 1-5, 6-10, and 11-15,respectively. Visual representation may include, for example, color. Forexample, value ranges A, B, and C, may be assigned colors blue, green,red, respectively. Value ranges A, B, and C may be provided manually bya user or automatically by the seed picking algorithm or by any othermethod. Although three regions and three value ranges are described, anynumber of value ranges and regions may be used. Typically the narrowervalue ranges A, B, and C are, the greater the resolution of attributedata is provided. Other methods of displaying attribute data may beused.

Attribute map 106 may be displayed with horizon map 104, for example, bydraping, overlaying, or adding points of attribute map 106 to horizonmap 104. Each point of attribute map 106 may provide attributes 110value or value range corresponding to one or more points picked fromseismic data 103 and may be displayed with those points.

Displaying attribute map 106 with horizon map 104 may provide insightfulinformation to a user, for example, a petroleum explorationprofessional, into the nature of geological structures from whichseismic data 103 is collected. In some embodiments, seismic data 103collected from regions containing faults, may impede or alter thepropagation of a picking algorithm, resulting in discontinuities orabrupt changes in the generation count of spatially adjacent pickedpoints in the neighborhood corresponding to the fault. For example,adjacent points may have very different iteration numbers. Attribute map106 may include value ranges A, B, and C, for attribute 110, measuring,for example, the generation of picked point. The abrupt changes in thegeneration measure may correspond to neighboring points falling intodifferent value ranges A, B, and C, and therefore into different regions310, 320, and 330 in attribute map 106. The change in regions 310, 320,and 330 may be visually represented by a change in the visualrepresentation associated with each of value ranges A, B, and C. Users,such as, petroleum exploration professionals may observe boundaries ofregions 310, 320, and/or 330. For example, a high density of suchboundaries, or boundaries with an odd shape, may indicate possiblelocations of faults, facies or other geological boundaries. For example,discontinuities in the surface, such as faults, may be highlighted byvisual representations of attributes 110, such as the artificialillumination on the 3D topographic surface and discontinuities in thegeneration count or iterative number indicated by discontinuities incolor. Where the colors are continuous there may be a grain to the colorchanges which indicates the direction of propagation of the algorithmused. For example, such a visual representation may be a change in coloracross a spectrum, from blue to green to yellow. The difference in theiterative number of neighboring points may be shown as a visual orgraphical representation such as for example a difference in the coloror brightness of multiple lines and/or the width of the lines. The linesmay be replaced with for example dots and/or clustered dots and thedifferences may be represented by for example the density of the dots.Columns may be used with the height of the columns representing thedifference in the number of steps.

Each of FIGS. 3 and 4 is a graphical illustration of an attribute mapand a horizon map, generated according to an embodiment of theinvention. In embodiments depicted in FIG. 3, for each picked point,attribute map 106 may display attribute 110, for example, an iterationnumber. The attribute may be displayed as, for example, a color,brightness, etc. In embodiments depicted in FIG. 4, for each pickedpoint, attribute map 106 may display a number of attributes 110, forexample, an iteration number and a number of points chosen by processingthe picked point. For each of FIGS. 3 and 4, attribute map 106 may bedraped onto, overlaid onto, or added to a 3D topographic horizon map104. For each point, attribute map 106 may display a visualrepresentation associated with an attribute 110 value or value range.For example a number of generations, iterations, or picks, or a range ofthese numbers, may be associated with a visual attribute such as color,brightness, etc. Other point attributes may be associated with othervisual attributes.

FIG. 5 is a graphical illustration of an attribute map displayed with ahorizon map, according to one embodiment of the invention. Attribute map106 may be draped onto, overlaid onto, or added to a 3D topographichorizon map 104. Attribute map 106 may display attribute 110, forexample, the number of points picked resulting from one or more startpoints or seed points 120, using a picking algorithm. Threshold valuesmay be set (e.g., manually by the user of automatically by horizonpicking module 102) so that only points with attribute 110 valuesgreater or equal to the threshold values, may be displayed in attributemap 106. For example, attribute map 106 may only display picked pointswith a number of resultant picks greater than the threshold values. Forexample, value ranges A, B, and C, may be, for example, 10-15, 16-20,and 21-25, respectively. The threshold value for being displayed inattribute map 106 is 10. Thus, picked points with attribute 110 valuesless than 10 may not be displayed in attribute map 106. The thresholdvalues for being displayed with the visual representation correspondingto A, B, and C, are 10, 16, and 21, respectively.

Attribute values above threshold values may be illustrated as the“river” lines in FIG. 5. FIG. 5 does not show the gradual change in thenumber of steps (or generations) that an algorithm takes to come to apicked point from its seed point, as shown in FIGS. 2, 3, and 4. Thisprovides a view much like a watershed which shows the direction ofpropagation of the pick algorithm for the entire horizon. Since thisparticular algorithm follows paths of maximum similarity for the seismictrace interval being analyzed this map may indicate the “grain” of theseismic data which in turn indicates geologic information about thisinterval.

Graphical or visual representations other than color, translucency,brightness, dots, columns, or lines may be used.

FIG. 6 is a graphical illustration of an attribute map and a horizonmap, generated according to an embodiment of the invention of thehorizon map. In some embodiments, attribute map 106 may include, forexample, structural and stratigraphic grain for showing the progressionof an iterative process, such as a seed picking algorithm, throughseismic data 103 according to one embodiment of the invention. Attributemap 106 may display attributes 110, including for example, the number ofpoints chosen by processing each picked point. The user may set thecolor scale to a threshold of any number of resulting picks so that onlyvery prolific picked points with large number of resultant picks areaccentuated. FIG. 6 may show prolific picks in black, less prolificpicks in green, then picks that are even less prolific in red andfinally the least prolific picks in magenta. Other colors or visualattributes may be used. Attribute data may be illustrated as the “river”lines in FIG. 6. This provides a view much like a watershed which showsthe direction of propagation of the pick algorithm across the horizonmap 104. Since this particular algorithm follows paths of maximumsimilarity for the seismic trace interval being analyzed this map mayindicate the “grain” of the seismic data which in turn indicatesgeologic information about this interval.

FIG. 7 is a flowchart illustration of a method for recording andpresenting horizon maps with selective attributes according to oneembodiment of the invention.

According to one embodiment of the invention as shown in FIG. 7, aniterative process, for example, a point picking algorithm may start forexample by choosing one or more or a set of seed points in a 3D seismicdata set, as indicated at operation 412. In one embodiment, this choicemay be made by a user; in another embodiment this may be doneautomatically by horizon picking software, for example, software 102(FIG. 1). A new set of points may be picked, which may be derived fromthe seed points, as indicated at operation 414, following an iterativeprocess or algorithm, for example, a seed picking algorithm, that may befor example known in the art. For example, the points adjacent to thecurrent seed point(s) may be chosen, based on certain criteria, andthese points may be seed points in the next iteration. A set of pointsmay include one or more points. For example, a set may include, forexample only one item.

To repeat the seed picking algorithm, each of the points in the new setof points may be set as a seed point and the algorithm may be repeated.In some embodiments, at each iteration the process may be applied topoints neighboring the points currently being processed. In the processof picking the new set of points, certain attributes associated withthese new points may be generated. For example, the iteration may berecorded, and those points processed or chosen on this iteration may beassigned an iteration number, or a number corresponding to thisiteration number. For example, the iteration number may be a numbercorresponding to the number of times the algorithm is applied orexecuted to pick the point. According to one embodiment of theinvention, these attributes may be saved or recorded as indicated atoperation 416.

According to one embodiment, the attributes may include, for example,the number of iterative steps or iteration number (also known asgenerations), which may indicate for example geological information onthe gradient or rate of change in lithology of the crust of earthbetween a picked point and its seed point. For example, each pickedpoint may be assigned an iteration number. According to anotherembodiment, the attributes may include, for example, the number ofpoints that have resulted from or have been found based on a precedingseed point or the number of descendants from the seed point. Thisattribute may contain for example two-dimensional information on thechange of lithology. According to another embodiment, the attributes mayinclude, for example, the direction of propagation of the seed pickingalgorithm and/or the order in which the points are picked, informationrelating to the azimuth directions of progression of the points picked.For example, at a particular picked point the attribute may be theaverage value of azimuth direction of the propagation or progression to,and from, the picked point.

As indicated at operation 418, the point picking process described aboveat operations 414 and 416 may be repeated until certain criteria suchas, for example, all the boundary points of a horizon map beinggenerated, are met.

According to one embodiment of the invention, after the completion ofthe point picking process, one or more attributes saved or recordedduring the picking process may be displayed selectively, as indicated atoperation 420. In one embodiment, attributes may be displayed as avisual representation of the relationship between the seed point andeach of the points in the new set of points. The display of selectiveattributes may help a user, for example, a petroleum explorationprofessional, identify geometric and geological information from thehorizon map generated by a computer system. It will be appreciated bypersons skilled in the art that the present invention is not limited towhat has been particularly shown and described hereinabove. Rather thescope of the present invention is defined only by the claims, which arepresented in the claim section.

What is claimed is:
 1. A method for processing 3D seismic data, themethod comprising: applying using a computer processor an iterativeprocess to a set of seismic data points, the process starting at a seeddata point and finding a set of next iteration seed points from amongthe set of points neighboring the seed point, the process continuingonly with next iteration seed points; recording using a computerprocessor for each of a set of seismic data points the number of pointsthat are found by the process when the point is used as a seed datapoint; and displaying each of the set of seismic data pointsrepresenting a subsurface of the earth according to a visualrepresentation of the number of points that are found by the processwhen the point is used as a seed data point.
 2. The method of claim 1,wherein the visual representation is a color.
 3. The method of claim 1,wherein the recorded number represents two-dimensional information onchange of lithology.
 4. The method of claim 1 comprising displayinginformation that relates to the direction of propagation with which theprocess picks points.
 5. The method of claim 1 comprising displayinginformation that relates to the average value of azimuth direction ofpropagation to and from the point.
 6. The method of claim 1 comprisingdisplaying for each point a plurality of visual representations, eachvisual representation corresponding to one of a plurality of attributesfor the point.
 7. The method of claim 6, wherein one of the plurality ofattributes is selected from the group consisting of: a number ofdescendants of a point, an iteration number corresponding to a number oftimes the algorithm repeated to process the point, and the direction ofpropagation of the horizon picking process.
 8. The method of claim 1,wherein the initial seed data point is selected by a user.
 9. A methodfor displaying 3D seismic data comprising: accepting using a computerprocessor an indication of a first point in a 3D seismic data set;executing using a computer processor a seed picking algorithm, using thefirst point for picking a set of second points from the data set;setting using a computer processor each of the points in the set ofsecond points as the first point and repeating the algorithm; assigningusing a computer processor to each point a number of points that arefound by the process when the point is used as a first point; anddisplaying each of a set of points representing a subsurface of theearth according to a visual representation of the number of points thatare found by the process when the point is used as a first point. 10.The method of claim 9 comprising for each point assigning an iterationnumber to each of the points, the iteration number corresponding to thenumber of times the algorithm repeated to process the point.
 11. Themethod of claim 9 comprising displaying information that relates to thedirection of propagation with which the algorithm picks points.
 12. Themethod of claim 9 comprising displaying information that relates to theazimuth of propagation with which the algorithm picks points.
 13. Themethod of claim 9, comprising: assigning a first value range associatedwith a first color and a second value range associated with a secondcolor; and displaying a point as the first color when the number ofpoints falls within the first value range and as the second color whenthe number of points falls within the second value range.
 14. A methodfor displaying 3D seismic data comprising: accepting using a computerprocessor an indication of a first point in a 3D seismic data set;executing using a computer processor a seed picking algorithm, using thefirst point for picking a set of second points from the data set;setting using a computer processor each of the points in the set ofsecond points as the first point and repeating the algorithm; assigningusing a computer processor an attribute to each of the points, theattribute being selected from the group consisting of: the number ofpoints that are found by the process when the point is used as a seeddata point and the average value of azimuth direction of propagation toand from the point; and displaying each of the points representing asubsurface of the earth according to a visual representation of theattribute for the point.
 15. A system for processing 3D seismic data,the system comprising: a processor for applying an iterative process toa set of seismic data points, the processor starting the process at aseed data point and finding a set of next iteration seed points fromamong the set of points neighboring the seed point, the processorcontinuing the process only with next iteration seed points; and amemory for recording for each of a set of data points the number ofpoints that are found by the process when the point is used as a seeddata point, wherein the processor is to display each of the set ofseismic data points representing a subsurface of the earth according toa visual representation of the number of points that are found by theprocess when the point is used as a seed data point.
 16. The system ofclaim 15, wherein the visual representation is a color.
 17. The systemof claim 15, further comprising an input device for accepting from auser the initial seed data point.